Merge branch 'main' of git.h3cx.dev:h3cx/fphysics

gravity.c

@@ -4,23 +4,22 @@
 #include <raylib.h>
 
 void gravity(universe_t *uni) {
-  mass_body_t body_1;
-  mass_body_t body_2;
-  for (unsigned int i = 0; i < uni->num_bodies - 1; i++) {
-    body_1 = uni->bodies[i];
+  const float dt = 1.0f / simx;
+  for (unsigned int i = 0; i < uni->num_bodies; i++) {
+    mass_body_t *body_1 = &uni->bodies[i];
     for (unsigned int y = i + 1; y < uni->num_bodies; y++) {
-      body_2 = uni->bodies[y];
-      float force =
-          simx * NEWTON_G * body_1.mass * body_2.mass /
-          (vec2_len(vec2_diff(body_2.position, body_1.position)) * TIMESTEP);
-      Vector2 acceleration =
-          vec2_normalize(vec2_diff(body_2.position, body_1.position));
-      Vector2 acceleration_1 = vec2_scale(acceleration, force / body_1.mass);
-      Vector2 acceleration_2 = vec2_scale(acceleration, -force / body_2.mass);
-      body_1.speed = vec2_sum(body_1.speed, acceleration_1);
-      body_2.speed = vec2_sum(body_1.speed, acceleration_2);
-      uni->bodies[y] = body_2;
+      mass_body_t *body_2 = &uni->bodies[y];
+      Vector2 separation = vec2_diff(body_2->position, body_1->position);
+      float distance_squared = vec2_dot(separation, separation);
+      if (distance_squared == 0.0f) {
+        continue;
+      }
+      Vector2 direction = vec2_normalize(separation);
+      float factor = NEWTON_G * dt / distance_squared;
+      body_1->speed =
+          vec2_sum(body_1->speed, vec2_scale(direction, factor * body_2->mass));
+      body_2->speed = vec2_sum(body_2->speed,
+                               vec2_scale(direction, -factor * body_1->mass));
     }
-    uni->bodies[i] = body_1;
   }
 }

main.c

@@ -7,7 +7,7 @@
 #include "magnetism.h"
 =======
 #include "objects.h"
->>>>>>> aa4f0dfe52bab37ef3bf82a47c44316c74c3ccbc
+#include "vec_utils.h"
 #include <bits/time.h>
 #include <math.h>
 #include <pthread.h>
@@ -35,9 +35,8 @@ void *physics(void *args) {
   universe_t *uni = (universe_t *)args;
   struct timespec ot, ct;
   while (true) {
-    printf("a");
     clock_gettime(CLOCK_MONOTONIC, &ct);
-    // gravity(uni);
+    gravity(uni);
     mechanics(uni);
     magnetism(uni);
     ot = ct;
@@ -64,10 +63,15 @@ int main(void) {
   const char *welcome_text = "Welcome to Fucked Physics!";
   universe_t universe = {0, NULL};
   universe.bodies = malloc(1024 * sizeof(mass_body_t));
-  universe.num_bodies = 2;
+  universe.num_bodies = 3;
+
+  universe.bodies[0] =
+      (mass_body_t){10000000000000.0f, 1000, {-0, 0}, {0, 0}, 200};
+  universe.bodies[1] =
+      (mass_body_t){100000000.0f, 0.1, {-10000.1, 0}, {0, -0.2}, 50};
+  universe.bodies[2] =
+      (mass_body_t){100000000.0f, 0.1, {10000, 0}, {0, -0.2}, 50};
 
-  universe.bodies[0] = (mass_body_t){100000000000.0f, 200, {0, 0}, {0, 0}};
-  universe.bodies[1] = (mass_body_t){100, 50, {500, 0}, {0, 2}};
   SetConfigFlags(FLAG_WINDOW_RESIZABLE);
   InitWindow(800, 450, "Fucked Physics");
   SetTargetFPS(120);
@@ -80,11 +84,17 @@ int main(void) {
       key_pressed = GetKeyPressed();
       switch (key_pressed) {
       case KEY_I:
-        v_scale += 0.1;
+        if (v_scale >= 0.1) {
+          v_scale += 0.1;
+        } else {
+          v_scale += 0.01;
+        }
         break;
       case KEY_O:
         if (v_scale > 0.1) {
           v_scale -= 0.1;
+        } else if (v_scale > 0.01) {
+          v_scale -= 0.01;
         }
         break;
       case KEY_LEFT:
@@ -102,23 +112,35 @@ int main(void) {
       }
     } while (key_pressed != 0);
 
+    if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON) ||
+        IsMouseButtonDown(MOUSE_RIGHT_BUTTON)) {
+      Vector2 mouse_pos = vec2_scale(
+          transform_to_center(vec2_scale(GetMousePosition(), -1)), -1);
+      mouse_pos = vec2_scale(mouse_pos, 1 / v_scale);
+
+      universe.bodies[universe.num_bodies] =
+          (mass_body_t){100000.0f, 0.1, mouse_pos, {0, 0}, 10};
+      universe.num_bodies++;
+    }
+
     if (canvas_offset.x + GetRenderWidth() * 0.5 / v_scale >
-        GetRenderWidth() * 5) {
+        GetRenderWidth() * 50) {
       canvas_offset.x =
-          -GetRenderWidth() * 0.5 / v_scale + GetRenderWidth() * 5;
+          -GetRenderWidth() * 0.5 / v_scale + GetRenderWidth() * 50;
     } else if (canvas_offset.x - GetRenderWidth() * 0.5 / v_scale <
-               -GetRenderWidth() * 5) {
-      canvas_offset.x = GetRenderWidth() * 0.5 / v_scale - GetRenderWidth() * 5;
+               -GetRenderWidth() * 50) {
+      canvas_offset.x =
+          GetRenderWidth() * 0.5 / v_scale - GetRenderWidth() * 50;
     }
 
     if (canvas_offset.y + GetRenderHeight() * 0.5 / v_scale >
-        GetRenderHeight() * 5) {
+        GetRenderHeight() * 50) {
       canvas_offset.y =
-          -GetRenderHeight() * 0.5 / v_scale + GetRenderHeight() * 5;
+          -GetRenderHeight() * 0.5 / v_scale + GetRenderHeight() * 50;
     } else if (canvas_offset.y - GetRenderHeight() * 0.5 / v_scale <
-               -GetRenderHeight() * 5) {
+               -GetRenderHeight() * 50) {
       canvas_offset.y =
-          GetRenderHeight() * 0.5 / v_scale - GetRenderHeight() * 5;
+          GetRenderHeight() * 0.5 / v_scale - GetRenderHeight() * 50;
     }
 
     BeginDrawing();
@@ -128,9 +150,9 @@ int main(void) {
       Vector2 body_position = vec2_scale(universe.bodies[i].position, v_scale);
       body_position = vec2_sum(body_position, scaled_offset);
       DrawCircleV(transform_to_center(body_position),
-                  universe.bodies[i].radius * v_scale,
-                  (Color){((256 / universe.num_bodies) * i) % 256,
-                          255 * (i % 2), 255 * (i % 2) * (i % 3), 255});
+                  universe.bodies[i].draw_radius * v_scale,
+                  (Color){((256 / universe.num_bodies) * i) % 256 / 2,
+                          255 * (i % 2) / 2, 255 * (i % 2) * (i % 3) / 2, 255});
     }
 
     DrawText(welcome_text, center_x_text(welcome_text, GetRenderWidth(), 20),

mechanics.c

@@ -48,8 +48,8 @@ void collide(mass_body_t *a, mass_body_t *b, const Vector2 normal,
 }
 
 void collide_rigid(mass_body_t *a, float restitution) {
-  float max_x = GetRenderWidth() * 10 / 2.0f - a->radius;
-  float max_y = GetRenderHeight() * 10 / 2.0f - a->radius;
+  float max_x = GetRenderWidth() * 100 / 2.0f - a->radius;
+  float max_y = GetRenderHeight() * 100 / 2.0f - a->radius;
 
   if (a->position.x > max_x) {
     a->position.x = max_x;
@@ -86,7 +86,7 @@ void mechanics(universe_t *uni) {
         body_2 = uni->bodies[y];
         collision = body_collision(&body_1, &body_2);
         if (!vec2_is_null(collision)) {
-          collide(&body_1, &body_2, collision, 1.0);
+          collide(&body_1, &body_2, collision, 0.99);
         }
         uni->bodies[y] = body_2;
       }

objects.h

@@ -7,6 +7,7 @@ typedef struct {
   float radius;
   Vector2 position;
   Vector2 speed;
+  float draw_radius;
   float charge;
 } mass_body_t;